Werner Syndrome (WS) is an autosomal recessive disorder with a complex phenotype. The disorder manifests itself in premature occurrence of age-related diseases and premature appearance of some of the physical features of normal aging. The onset of symptoms usually occurs after adolescence. The disorder progresses throughout life and typically patients have a shortened life expectancy with a modal age of death at 47. The prevalence of Werner Syndrome is estimated for heterozygotes to be 1-5 per 1,000 individuals, and for homozygotes to be 1-22 per 1,000,000 individuals.
Clinical symptoms of Werner Syndrome include both a prevalence of age-related diseases and physical features of aging. Such diseases include arteriosclerosis and heart disease, both benign and malignant neoplasms (usually sarcomas), diabetes mellitus, osteoporosis, and ocular cataracts. The physical appearance of WS patients is often manifest as a short stature, premature graying or loss of hair, hypogonadism, altered skin pigmentation, hyperkeratosis, tight skin, bird-like facies, cutaneous atrophy, cutaneous leg ulcers, and telangiectasia. Most of these diseases and features are present in from 40-90% of WS patients. Diagnosis of WS relies mainly upon the appearance of a certain number of these diseases and features. One biochemical test, excessive excretion of hyaluronic acid in urine, may also be used to assist diagnosis.
In addition to the noted signs and symptoms of aging, Werner Syndrome mimics normal aging as evidenced by the replicative potential of fibroblasts isolated from WS subjects. Replication potential of fibroblasts is reduced in these patients compared to fibroblasts isolated from age-matched controls, and is comparable to the replicative potential of fibroblasts taken from elderly subjects. Moreover, an increased mutation rate has been described in WS patients. Such abnormality is manifest as chromosomal instability, such as inversions, reciprocal translocations, deletions, and pseudodiploidy, and as increased mutation rate at the hypoxanthine phosphoribosyl transferase (HPRT) gene.
Werner Syndrome has been recognized as an autosomal recessive disorder. Goto et al. (Goto et al., Nature 355:735-738, 1992) mapped the WS gene onto the short arm of chromosome 8, using 21 affected Japanese families. The gene is located between marker D8S87 and ankyrin (ANK1). More recently, more refined mapping has pinpointed the WS gene to a region between marker D8S131 and D8S87, an 8.3 cM interval. Identification of the gene and gene product should add considerably to understanding the basis of Werner Syndrome and enable biochemical and genetic approaches to diagnosis and treatment.
The present invention provides a novel, previously unidentified gene for Werner Syndrome and compositions for diagnosis and treatment of WS, and further provides other related advantages.